Return power optimization strategy of DAB converter based on model predictive control

Dual active full bridge (DAB) converter produces large return power under traditional phase shift modulation, and its dynamic characteristics are poor. For purpose of solv the above problems, this paper proposes a return power optimization method combining the output voltage model prediction of DAB converter based on EPS modulation and the Lagrange multiplier method. Through in-depth analysis of the mechanism of return power generation, the mathematics model of power of DAB converter is built. The model prediction equation of output voltage of DAB converter is obtained by state space averaging method, and the return power is suppressed by Lagrange multiplier method. Finally, the circuit model is built to verify the analysis conclusion, and these results are compared with those of the traditional SPS modulation and EPS modulation. The results demonstrate that this method can significantly inhibit the return power of the DAB converter, and can effectively improve its output properties.